Fill a wok 3/4 of the way up with water and place over high heat. Bring the water to a simmer.
Place the fish on a plate. Cut 5 or 6 slits into the skin on both sides. Season the fish with salt and freshly ground white pepper.
Place a few pieces of ginger into the slits of the fish and stuff the cavity with the remaining ginger and the four sliced shitake mushrooms. Pour the Shaohsing rice wine over the fish and then place the fish in a bamboo steamer and close the lid.
Place the steamer over the simmering water in the wok and steam for 10 to 12 minutes until the fish is cooked and the flesh flakes apart with a fork.
After ten minutes, sprinkle the spring onions and the sliced wild mushrooms on top of the fish and steam for two minutes more before serving. Serve immediately with Jasmine rice.
Cook’s Note: Also pairs well with a side of stir-fried vegetables such as bok choy or kai lan.